Mainly used for night driving, automotive headlamps provide the best visual effect for the driver in the process, which requires the lamps to have excellent lighting effects. With both headlamps on for lighting, the lamps should possess the property to enable the driver to watch traffic obstacles clearly within 100 meters ahead, with the beam at the forward direction and the direction of principal optic axis being lower. The condition of high and low beam shape and irradiation direction play an important role in safe night driving, because in the actual traffic environment, when two cars in the opposite directions encounter, the headlamp's glare may cause the driver to dazzle, which may be at risk of traffic accidents. At present the major solution to this is to switch between the high and low beam, that is, to use different headlamps according to different situations to unify the contradictions mentioned above.
Since the irradiation direction and relative position of high and low beam have fixed requirement, to adjust the product into consistency, an economical and practical adjusting device for automotive lamp manufacturers should be needed. Currently to adjust the relative position of high light of high beam shape to low beam shape, the common method is to separately dispose the high beam unit and low beam unit to independent brackets, each of which is disposed with a fixed fulcrum structure relative to lamp body as well as two adjustable points that can adjust along forward and backward direction. In this way, the adjustment to the relative position of the high light of the high beam shape to the low beam shape is implemented by separately adjusting the beam angle of high and low beam, which incorporates the principle that three non-collinear points determine a plane.
The deficiency of this method lies in the large-scale space, because each of the high beam unit and the low beam unit has a fixed bracket disposed with fixed fulcrum as well as two adjustable points that can adjust along forward and backward direction, among which the distance is above 80 mm to one another.
Another deficiency is that to meet the lawful requirement for beam angle of low beam, the low beam unit must be adjusted in upward, downward, leftward and rightward angles after the automotive headlamp is disposed on the automotive frame. After the beam angle of low beam unit has been adjusted, the high light of high beam shape will deviate from low beam shape because high beam unit and low beam unit belong to different brackets and adjustment systems.